2018 Audi S8 Sedan

8.0

Overview

The Audi A8 has been Audi's flagship sedan ever since it was introduced in the 90s. It offers exquisite comfort and a lot of power. And if you think that's all the A8 has to offer, think again. The 2018 Audi S8 Plus is the sportier version of A8 that takes its performance to the next level.

The S8 only comes in the Plus trim. Its base price starts at $115,900. Its hood plays home to a 4-liter twin-turbocharged V8 that produces a massive 605hp. This engine is complemented by an equally able 8-speed automatic transmission that powers all four wheels.

Aside from the ancient infotainment system, the Audi S8 oozes style and luxury both inside and out. Competing with giants like the Mercedes AMG S63 and the BMW ALPINA B7, the Audi S8 makes sure that it provides an overall amazing and exhilarating experience that leaves the driver and passengers in both rows thoroughly satisfied.

plus quattro 4dr Sedan AWD (4.0L 8cyl Turbo 8A)

Expert Review

carhp editorOctober 3, 2018

8.0

Overall Rating

8.0/10Features

9.0/10Engine

6.5/10Fuel Economy

8.1/10Interior

7.4/10Exterior

The 2018 Audi S8 only comes in the sole Plus trim. Its base price starts at $115,900. Its hood plays home to a 4-liter twin-turbocharged V8 that produces a massive 605hp. This engine is complemented by an equally able 8-speed automatic transmission that powers all four wheels.

Features

8.0/10

The 2018 Audi S8 only comes in Plus trim. It uses a powerful V8 engine that powers all wheels through an eight-speed automatic transmission. The S8 is the high performing version of the full-size Audi A8 sedan.

Since there are no trims to choose from, our recommendations are concerned with the optional packages. The Executive Plus adds extra safety features like lane departure warning and forward collision warning and is highly recommended, especially in cold climatic conditions.

Engine

9.0/10

“Mash down on the throttle, feel the eight-speed automatic dicing and slicing all 517 pound-feet of torque (553 lb.-ft. when overboost kicks in), and this sumptuously appointed, $148,000 executive’s chariot will blast from 0 to 60 mph in, says Audi, just 3.7 seconds. No way. It’s quicker than that. I’ve driven some seriously fast machinery lately and the S8 Plus is right there with all of them. With Quattro all-wheel drive, the S8 simply explodes off the line, all four tires biting into the asphalt, the V-8 screaming to its 6,800-rpm redline, stupefied Corvette drivers exclaiming, “What the hell was that?!” – Auto Mobile Mag

Engine and Transmission

The 2018 Audi S8 Plus uses a powerful 4-liter turbocharged V8 that produces 605hp and 517 lb.-ft. of torque. The engine is mated to an eight-speed automatic transmission. Audi’s Quattro All-Wheel-Drive is standard. Though the S8 doesn’t generate as much torque as its rivals with the overboost engaged it adds another 36 lb.-ft. of torque.

Models

Audi S8 Plus

BMW ALPINA B7 xDrive Sedan

Mercedes-Benz AMG S 63 4MATIC

MSRP

$115,900

$138,800

$147,500

Engine

4-liter twin-turbocharged V8

4.4-liter twin-turbocharged V8

4-liter twin-turbocharged V8

Transmission

8-speed automatic

8-speed automatic

9-speed automatic

Power

605hp @ 6100rpm

600hp @ 5750rpm

603hp @ 5500rpm

Torque

517 lb.-ft. @ 1750rpm

590 lb.-ft. @ 590rpm

664 lb.-ft. @ 2750

As far as power goes, the S8, BMW ALPINA B7, and the Mercedes-Benz AMG S63 are neck to neck, with the S8 being a tad ahead. But the BMW and Mercedes generate a lot more torque. The AMG S63 generates 664 lb.-ft. of torque. That’s 147 lb.-ft. more than the S8!

The S8’s V8 delivers more power than BMW’s or Mercedes’ V8 but is far behind in torque. It is worth remembering, though, that the S8 is quite cheaper than the other two. The BMW is $23,000 more expensive, and the Mercedes costs $9,000 more!

Acceleration

The S8 is the sportier version of Audi’s A8 sedan. The A8 is already established as a smooth and quick, and the S8 takes that performance even further. The 8-speed automatic transmission shifts effortlessly on all turfs. Whether you are on open roads or starting from a stop sign, the 2018 Audi S8 will give any car a run for its money.

Models

Audi S8 Plus

BMW ALPINA B7 xDrive

Mercedes-Benz AMG S63

0-60 MPH

3.3 sec

3.6 sec

3.4 sec

Quarter mile

11.6 sec

11.9 sec

11.6 sec

Engine Displacement

4L

4.4L

4L

Emission (Tons/yr of CO2 Emissions @ 15K mi/year)

9.8

9.3

8.8

The few HP’s advantages that the S8 has over the ALPINA B7 and the Mercedes AMG S63 allow it to pick up faster than them by a few milliseconds. In the 0-60mph test, Audi’s 3.3 seconds time is ahead of the Mercedes by a millisecond and BMW by 3 milliseconds. At the quarter mile, the Mercedes catches up with S8 with a time of 11.6 seconds. BMW stays behind by 3 milliseconds.

Handling and Steering

The 2018 Audi S8 Plus is a driver’s car. It dances around corners with a quickness and precision you wouldn’t expect from a sedan this size. The standard air suspensions and all-wheel-drive provide it with the degree of comfort and finesse that Audis are known for. The cabin is quiet and comfortable, which adds to S8’s luxury-cum-performance image.

Braking

The S8 Plus is a performance-oriented sedan, and there is no point of a fast car that can’t be controlled and stopped. The 2018 Audi S8 has one of the biggest front brakes in the class which allow it to stop quickly. The brake pedal provides a nice feel and is quite responsive.

Model

Audi S8 Plus

BMW ALPINA B7 xDrive

Mercedes-Benz AMG S63

Brake Front(in)

15.7

15.5

15.4

Brake Rear(in)

14

14.5

14.4

Curb Weight (lbs.)

4685

4820

4564

70-0 MPH (ft.)

156

151

157

The quickest to come to a stop is the BMW ALPINA B7 which only takes 151 feet to come to a halt from 70mph, even though it is the heaviest amongst the competition. The Mercedes takes 157 feet to stop, a foot more than the Audi.

Fuel Economy

6.5/10

With great power comes great responsibility. So when you enjoy the great power of 2018 Audi S8, just remember you have the great responsibility of visiting the gas pumps every now and then. The S8 is reasonably thirsty, given that is glides like a sports car.

Model

Audi S8 Plus

BMW ALPINA B7 xDrive

Mercedes-Benz AMG S63

mpg (city)

14

16

17

mpg (highway)

24

25

26

mpg (combined)

18.5

20

21

The Audi S8 lags behind the rivals in the mileage department. The most economical amongst these rivals is the Mercedes-Benz AMG S63. Its combined economy of 21 is ahead of BMW by 1mpg and Audi S8 by 2.5 mpg.

Interior

8.1/10

“Though its design is a few years old, the S8's interior still displays an attention to detail and cohesion in design. If a surface isn't high-quality leather or an attractive trim piece, it's probably simulated suede. And it's all customizable” – Edmunds

Seating and Comfort

When it comes to comfort, very few can match what the Audi offers. The seats consist of Volcana leather upholstery, heated and 22-way power-adjustable front sport/comfort seats. The seats include power lumbar adjustment, ventilation, massage function, memory, and diamond stitching.

Model

Audi S8 Plus

BMW ALPINA B7 xDrive

Mercedes-Benz AMG S63

Passenger capacity

5

5

5

Passenger Volume (ft.3)

115.1

N/A

N/A

Front (Head/Shoulder/Leg) (In.)

37.2/59.1/41.4

39.9/61.2/41.4

39.7/59.7/41.4

Second (Head/Shoulder/Leg) (In.)

38.1/57.8/38.7

38.9/61/44.4

39.2/59.1/43

Even the back row seats have a few surprises. Upgrading the rear seats add heated, ventilated, power-adjustable, and massage seats. Both rows are exceptionally comfortable and roomy. Although the S8 doesn’t have a long wheelbase version, there is enough legroom in the back.

The standard infotainment system installed with the 2018 S8 is the same as in A8. It includes Audi's MMI infotainment interface, a 14-speaker Bose audio system, an in-dash DVD player, navigation, satellite radio, HD Radio, Bluetooth, and iPod integration. It can be upgraded to 19-speaker Bang & Olufsen audio system, a rear-seat DVD entertainment system with dual 10-inch screens.

Though the infotainment system is fairly easy to understand, it does feel a bit dated. Even the new A4 has a better and newer infotainment system. Not only is it ancient, but it’s also set at an awkward angle and reaching some controls while driving is really infuriating.

Cargo

For a vehicle of this size, the 2018 Audi S8 has a rather tight trunk. It is well below the class average. While all companies oscillate around 18-19 cubic feet, with some providing, even more, the Audi doesn’t match its rivals in the trunk department. But Audi has a lot of little storage spaces inside the cabin.

Model

Audi S8

BMW ALPINA B7 xDrive

Mercedes-Benz AMG S63

Volume (ft.3)

14.2

18.2

18

The ALPINA B7 and the S63 provide 18.2 and 18 cubic feet of storage respectively. Audi’s 14.2 cubic feet of storage is nowhere near the rivals. So you can travel comfortably and fast in the Audi, but don’t expect it to be too accommodating of your luggage.

Exterior

7.4/10

“The A8 is only available in one length -- long wheelbase -- and comes in at 207.4 total inches. The S8 is a bit shorter and easier to park at 202.6 inches. One of the easiest ways to distinguish the 2018 S8 performance model is to look for the wide quad tailpipes in back.” – Kelley Blue Book

Design and Dimensions

The A8 only comes in the long wheelbase version, but the 2018 Audi S8 is only available with the normal wheelbase. It is shorter than the BMW ALPINA B7 and the Mercedes S63. But the S8 has a wider stance than either of the two, and it also stands higher than the BMW, though Mercedes is 1.6 inches higher.

Safety

Like most companies’ top end models, the Audi S8 doesn’t go through crash tests conducted by the Insurance for Highway Safety or the National Highway Traffic Safety Administration. Crashing such a masterpiece is a crime, and NHTSA and IIHS seem to agree with us!

Competition

Audi S8 Plus VS BMW ALPINA B7 xDrive

The ALPINA treatment has turned the 7 series into a faster, but a barely docile hyper sedan. It offers fun handling and powerful acceleration. But it can’t match S8’s sporty acceleration. The S8 provides an experience that matches BMW’s fun and outperforms it in terms of style and power.

The BMW has some more advantages, like a roomier trunk, an intuitive infotainment system, and a lot more torque generation. But overall, given that it costs considerably more too, the S8 provides more value-for-money and an overall experience.

Audi S8 Plus VS Mercedes-Benz AMG S63

Usually, the cars that are competing for head to head are quite close in dimensions. But the Mercedes-Benz S63 is about 4 inches longer than the 2018 Audi S8, it is taller, and has a longer wheelbase. The evidence can be found inside and out.

Both cars provide amazing acceleration, luxurious cabin, and the style quotient. It is worth noting, though, that Mercedes provides all this at a much higher cost than the Audi.

Final Verdict

The S8 takes the comfort and style of the A8 and marries it to raw power and hair-raising acceleration. It costs north of a thousand grand but is still considerably cheaper than rivals like BMW ALPINA B7 and the Mercedes AMG S63.

Though its infotainment is a bit dated, its fuel economy is not as great as the rivals, and its trunk is pretty tight for its class, these flaws are almost erased once you put your foot on the gas pedal and feel your body pushed back into the seat. So sit back into the comfy seats, enjoy Audi’s luxurious cabin, and watch the world fly back through your windows!